"Even though I've never attempted the New York Times crossword puzzle or solved the Rubik's Cube, I couldn't put down The Puzzler."--Gretchen Rubin, author of The Happiness Project and Better Than Before What makes puzzles-jigsaws, mazes, riddles, sudokus-so satisfying? Be it the formation of new cerebral pathways, their close link to insight and humor, or their community-building properties, they're among the fundamental elements that make us human....